#div1::after{
  position: absolute;
  width: 100px;
  height: 100px;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  border-radius: 50%;
  background: radial-gradient(circle, rgba(0,0,0,1) 10%, rgba(255,255,255,1) 10%, rgba(255,255,255,1) 100%);
  background-color: rgb(154, 189, 245)
}